Bubbles, or other voids in coverslip adhesive used to hold coverslips to individual microscope slides, add extra air to glass surfaces and in other ways change the way objects are resolved by a microscope objective. For a system making precise measurements of objects in the specimen, these changes make measurements on the objects within the voids unreliable and therefore unusable.
The edges of the bubbles are themselves resolved as heavy dark objects which are not of interest to the system analyzing the specimen. Therefore, it is undesirable to spend time trying to focus and analyze the bubble edges at high magnification.
The prior art has detected bubbles within liquids flowing through tubes, in essence, a one dimensional problem. The common technique is to use a photosensor of some type which detects the boundary between the liquid and the bubble.
Referring not to FIG. 11, a typical microscope slide 10 is shown exhibiting voids or bubbles in the coverslip adhesive. The microscope slide 10 comprises a plate 12 including an identification area 11. A coverslip 14 is placed over a specimen using an adhesive. The placement of the coverslip 14 sometimes unfortunately results in bubbles forming in the adhesive. In this example bubbles are shown as circular bubble 15, irregular bubble 17 and edge bubble 16. Since the perimeters of such bubbles usually exceed the field of view of microscopes used to view such slides, the size or existence of such bubbles often goes undetected.